Remove useless fallback

Remove the line, since we already tried location.raw_comment() first.
Originally the last `or_else` branch
debug printed `location.raw_comment()`, but the print
was removed in c94367c.

Author: jschwe

bindgen/ir/item.rs

@@ -1590,10 +1590,7 @@ impl Item {
             canonical_def.unwrap_or_else(|| ty.declaration())
         };
 
-        let comment = location
-            .raw_comment()
-            .or_else(|| decl.raw_comment())
-            .or_else(|| location.raw_comment());
+        let comment = location.raw_comment().or_else(|| decl.raw_comment());
 
         let annotations =
             Annotations::new(&decl).or_else(|| Annotations::new(&location));